1. Field of the Invention
The present invention relates to an image pickup apparatus having an imaging device and an optical member such as an optical filter, and more particularly, to an image pickup apparatus capable of preventing foreign matters such as dust from adhering to an optical member.
2. Description of the Related Art
An electronic image pickup apparatus such as a digital still camera or a video camera is excellent in immediacy and in compatibility with a personal computer and therefore has been rapidly widespread. The electronic image pickup apparatus having an imaging device on which an object image is formed by an image pickup optical system such as lenses and by which the object image is photoelectrically converted into image data. In general, an optical member such as an optical low pass filter or an infrared cut filter is disposed between the imaging device and the image pickup optical system.
In the image pickup apparatus, foreign matters such as dust sometimes adhere to the imaging device or to the optical member. For example, in a digital single-lens reflex camera having a replaceable lens, dust or the like, which is generated in a mechanical operation part such as a shutter or a quick return mirror, adheres to a surface of a cover glass of the imaging device or to a surface of the optical member such as an optical filter, which are disposed near the operation part. Upon lens replacement, foreign matters such as dust enter into the camera main unit through an opening of a lens mount and adhere to e.g. the optical member. In that case, images of foreign matters are included in a captured image, resulting in a degraded appearance of the image.
To obviate this, there has been proposed an image pickup apparatus capable of removing foreign matters such as dust adhered to an optical member, which is disposed in front of an imaging device (see, for example, Japanese Laid-open Patent Publication No. 2009-33441).
In the proposed image pickup apparatus, an electrically conductive tape affixed to a surface of the optical member is pressed by an electrically conductive elastic member to make the potential at the surface of the optical member equal to that of the electrically conductive elastic member connected to a reference potential portion of a camera main unit, thereby making the potential at the surface of the optical member equal to the reference potential, whereby dust or the like can be prevented from adhering to the optical member due to electrostatic force generated when the surface of the optical member is charged.
However, the above-described construction requires an assembly step of affixing the electrically conductive tape to the optical member. The electrically conductive tape is generally soft and small in elasticity, and is therefore easy to be deformed during the assembly work. In addition, the electrically conductive tape is small in size. This results in poor assembly workability.